Transmission



D. W. KELBEL TRANSMISSION Feb. 5, 1952 Filed Dec. 22. 1947 INH lm* .faz/enfer.' D naald .e'eZ

Patented Feb. 5, 1952 rRANsMissIoN Y Donald W. Kelbel, Muncie, Ind., assignor to Borg- Warner Corporation, Chicago, Ill., a corporation of Illinois Application December 22, 1947, Serial No. '193,261

(o1. vir- 732) f 2 Claims.

My invention relates to transmissions specifiautomotive transmissions comprising hydrodynamic torque transmitting devices.

It is an object of my invention to provide an improved transmission of this type which includes a friction coupling which is so arranged with the parts of the transmission that it may be utilized for completing the drive both in forward and in reverse.

It is another object of the invention to provide a transmission comprising a hydrodynamic coupling device and which may be shifted from a low speed forward drive to a high speed forward drive by the disengagement of one friction coupling and the engagement of another. More particularly, it is an object to provide such a transmission which comprises a hydraulic torque converter, a friction brake for the reaction element of the torque converter, a coupling for connecting a reaction member of a gear set with the reaction element whereby both may be braked, and a second coupling for use instead of the last-named coupling for locking up the gear set to provide a direct drive.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above-stated objects and such other objects as will appear from the following detailed description of a certain preferred embodiment illustrated in the accompanying drawing in which the figure shows a longitudinal sectional view of a transmission embodying the principles of the invention with certain portions of the transmission being shown diagrammatically.

Referring now to the drawing, the illustrated transmission comprises a driving shaft Ill adapted to be connected to an engine (not shown) of a vehicle in which the transmission is installed, a driven shaft I I adapted to be connected with the driving wheels (not shown) of the vehicle, andan intermediate shaft I2. The shaft i2 is piloted in both the shafts IIJ and II as shown, and the shaft II is rotatably disposed within the transmission casing I3 by means of bearings I4 and I5.

The transmission comprises in general a hy- 2 and comprises a bladed impeller 23, a bladed runner or driven element 24 and a bladed stator or reaction element 25. The impeller 23 comprises a housing 26 which forms the principal part of the housing for the torque converter. and this housing contains a fluid, such as oil, by means of which the runner 24 is driven by the impeller 23. The runner 24 is splined to the intermediate shaft I2 and the impeller 23 is connected to be driven by the planetary gear set I'l as will now be described.

The planetary gear set II comprises a ring gear 2, a sun gear 28, a set of planet gears 29 in mesh with the ring gear and a second set of planet gears 30 in mesh with the sun gear and with the planet gears 29. The planet gears 29 and 3I are rotatably disposed on a planet gear carrier 3i which is xed with respect to the mpeller housing 26 as shown. The sun gear 28 is splined on the shaft l2 as shown. The ring gear 2l is connected with the driveshaft III through a vibration dampener 32 which in turn is fixed to a flywheel 33 carried by the drive shaft I0. The vibration dampener 32 may be of any suitable construction and may comprise springs 34 disposed between opposite parts 35'and 36 of the dampener.

A one-Way clutch`31 is provided between the planet gear carrier 3I and the intermediate shaft I2 and comprises rollers 38 disposed between opposite cam surfaces 39 and 40. The roller clutch is so constructed as to overrun and transmit no drive when the drive shaft I' is rotating in the forward direction as is indicated by the arrow 4I and the intermediate shaft .I2 is rotating in the same direction at the same or a less speed; however, the roller clutch 31 will engage if the intermediate shaft I2 is rotated in the direction as indicated by the arrow 4I and the shaft Il) is not being driven by the engine of the vehicle.

The stator 25 is mounted by a combination bearing and roller clutch 42 on a tubular, shaft 43 disposed on the intermediate shaft I2 and which is rotatably mounted within the transmission casing I3 by means of a bearing 44 and within the impeller 26 by means of a bearing 45. The assembly 42 comprises rollers 46 disposed between facing cam surfaces 41 and 48 and the arrangement of the cams is such that when the shaft 43 is held stationary, the roller clutch will engage to prevent the stator 25 from rotating in the Vreverse direction, that is in the direction opposite to that indicated by the arrow 4 I.

The assembly of the hydrodynamic torque converter I6 and the planetary speed-up gear set II is very similar to the assembly of the saine set Il. Torque is thus transmitted to the runner 2li and the shaft I2, and when these partsibegin.l

to rotate and increase in speed, the speeds of the impeller 23 and the shaft' 13 become'more nearly equal. the direction of ow of uid within the torque converter and provides a torque errthe-runner.L

il which is greater than that impressedron the impeller 23, and this condition obtains until the runner 24 rotates at a substantial speed whereupi'nnthe' stator`25ibegins to rotate'in theforward directiony and the converter functions fromrthis Ytime' forwardJ as'a simple Huid* coupling in which tlrereisenoA increase irrtorque` between' the driving and drivenelements.

The stator 25 functions to'change engaged. Since the friction brake engaged, vthe' stator 2i5'iswxfree to 'rotate as it 4 The transmission provides a neutral condition, low and direct drives forward and a reverse drive. In the neutral condition the friction clutches 2| and 22 and the friction brakes I9 and 20 are dis- I9 is dis- `will and since the two"clutches"2'l "and 22 and the brake are disengaged, none of the mem- 'bers of the planetary gear set I3 functions as a reaction member and the drive between the shafts I2 and I I through the gear set is broken.

' For4 low' speed forward drive the brake I9 is engaged' and the clutch 2I is engaged. Engagement of' the'brake I9 stops the shaft 43 and thereby. the. stator; from rotation and torque is thus impressed upon the intermediate shaft I2 The "planetary gear set 1'8" comprises a ring geaii9,`a sun gear 50; a' Aset oflplanet gears 5I in rneshf with the ring gearanda set of planet gearsl` '52 in mesh with'the 'sun gear and' with the planet' gea'rs5l'.A` The planet gears 5I and 52 are mounted on a carrier' 53"which isl splined to 'thev intermediate shaft`V I2;A rPhe ringgear 49 is connectedwith thel driven shaft" II', asshown The sun gear' 50 is connected with both of` the multiple plate friction clutches' 2'I an'd22. The l clutch 2lv comprises clutch 'p1ates54`sp1ined" to a'd'rumv 55 and clutch plates`56i splined to a drum 5T.'The drum 5T is connected with the sun gear 59 and the drum 55 is connected with'theshaft lf3". The multiple platefriction clutch 22o com*- prisesl friction platesV 58' splined'to a drum 55 and friction platesV 60 'splined-to' the vdrum 5'1"; The' drum '59" is connected with` the carrier 53 for the planet gears 5I' and 52 as'shown'.

'rtiiuidpressure` actuated piston E'I is provided centric shafts in the transmissionmay be pron vided vfor supplying fluid t'o the pistonsliL and 6'4".

The. friction brakes I9 and' 20 areofthe ordi'- vnaryY friction band type and may' be actuated by suitable hydraulic motors, such as the motor 61 provided' for the brake 201 A fluid pressure pump 68 for supplying fluid under pressure for actuating the friction brakes and clutches is provided, and this pump is; driven fromthe impeller '23" through'v gears 69` and'V TU.

A fluidpump 'II' also for supplying' fluid under pressureA may .be provided and' thisjmay be driven by a gearf2 on the driven shaft I 'I' and a gear Inroperation, the.. transmission drives'haftrl is drivenfromlthe engine'(not shown)` of'the. ve-

hicle in which. the transmission is installedand the driven.l shaft II is connectedwith the driving wheels (notshown) of thevehicle. Tliedrive shaft I0 is kept in` rotation by the engine and the intermediate shaft I2 is driven from the -torque'converter ISand the planetari7 gear set I1 from the drive shaft I 0L from the' runner 2li. The sun gear 55 constitutes the reaction member of the planetary gear set` I-8;- however; this elementis not brakedxuntil the-frictionclutchZI is` engaged.Y Upon. engage.- mentof-v this friction ,clutch a power train is completed through the gear' set- I 38 beiwvecnthe shafts I-2- and I-I', driving the'shafttII at aflower speed than theshaft I2, and this-is the low speed forward drive of-the transmission. Either the brake-|`9 or theJ clutch- 2| 'mayi beengaged as gradually as-desiredafter-v theother haspreviously been engaged in order to completefthis power train-in a: gradual manner forfstarting:thevehicle aswill-beapparent. i f

The transmission may-1 be shiftedfrornl, 10W speed forward driveto-direct drive by disengaging the.l friction clutch=-2| and engaging the-clutch 22; Engagement. of the-Vclutclrzz has lthe effectof locking together for' unitary rotation. the; planet gear carrier 'i531 and. the sun. gear'. 51D so that"` the planet gear set IIlis locked uprandrthe driven shaft I @I is-dr-ivenat thesame--speedf-and in` a one-to-one ratio.-A from- `the.intermediate shaft I2'. With the--v clutch ZfZS-en'ga'gedthef transmission is thusin direct' drive.,` "l3h'e'.brake1` I9 is kept inl engagement'so. fthatrthe reaction'. element 5sof the hydrodynamic torque.y converter .isi available for torque. multiplication,*assuming that; the torque required' toy be transmitted-Li is: sufficient for suche` multiplicationi is vinY accordance with the1well-known. principles of operation of' such hydrodynamicL devices;

- ReversedriveLis-obtained by engaginglthefbrake 2 and theifriction: clutch 21;. 'Engagement of the7 frictionclutch;` 2-Ifl has: the eiect' of; coupling together theshaft/Jt andithesun gea-r1 55; and engagementoffthe-brakes2Uhastheeifectoffbraking the runner'k 214-which is: coupledto the carrier 53' through-the5sl'1afti I2. With' Vthe-runner 24 of the hydrodynamic' devicev If* being lfi'e'ldZ 'stationary rby meansof* the-brake 25, the' reaction memberV 25 is driven in-thefrevers'e direction, Aand this 'rotation is' transmittedthrough the' one -way clutch i12; the shaft 43, the drum-55, theclutch ZI", andthe ldrum 5T tothe son` geariil and', the ringkgear" 4.9i andtliereoyv tlieshaft I'I aredriven in the reversedirection ata speedlessthanthe speedof the shaft' 63; the reduction Virrspeedbeing brought about by the planetary' gear' setLI. Since both theclutchj 2'I`- and` thebrake 2:5are necessary for astartin reversedrive, this drive may be completed as gradually as desiredf'by lgradual engagement of,` either one of these two control parts. ,A

improvedftransmission advantageously provides' an absoluteneutral in which no torque' is transmitted' from the drive *shaftv to the driven shaft so thatthe vehicle in which the, transmis'- sion installed does not have a tendency to creep. The brake band I9 may be applied to condition the transmission for forward drive; however, due to the clutch 2l which may be held open until the accelerator of the vehicle is depressed, there is no braking action on the sun gear 5B and no torque is transmitted from the intermediate shaft 2 to the driven shaft Il. The same holds for reverse driveeven though the reverse brake 29 is engaged; nevertheless, no torque is transmitted between the shafts I2 and i i `until engagement of the clutch 2|.

I Wish it to be understood that my invention is not limited to the specific constructions, arrangements, and devices shown and described except only insofar as the appended claims may be so limited as it will be apparent to those skilled in the art that changes may be made without departing from the principles of the invention.

I claim:

1. In a transmission, the combination of a drive shaft, a driven shaft, a hydraulic torque converter comprising an impeller, a rotor, and a stator, said impeller being connected to be driven by said drive shaft, a planetary gear set, said gear set comprising a sun gear element, a ring gear element, a planet gear in mesh With said ring gear element, a planet gear in mesh with said first-named planet gear and with said sun gear element, and a carrier element for said planet gears, one of said elements being connected with said driven shaft and another of said elements being connected with said rotor, a friction brake for said stator, and a friction coupling for connecting the remaining one of said three elements with said stator whereby to be braked by said friction brake, said friction brake comprising a brake drum and a band surrounding the drum and adapted to engage it,

said friction coupling comprising a plurality ofl interleaved plates disposed Within said drum, and a friction clutch for connecting together two of said elements of said planetary gear set for locking up said elements for unity of rotation and comprising a plurality of interleaved plates disposed within a drum located adjacent said firstnamed drum and -coaxially therewith.

2. In a transmission, the combination of a drive shaft, a driven shaft, a hydraulic torque converter having an impeller, a rotor, and a stator, said impeller being connected to be driven by said drive shaft, a friction brake for said stator, a planetary gear set comprising a sun gear, a ring gear, a planet gear in mesh with said ring gear, a second planet gear in mesh with said first-named planet gear and with said sun gear, and a carrier for said planet gears, said ring `gear being connected with said driven shaft and said carrier being connected with said rotor, a friction coupling for connecting said sun gear vwith said stator whereby both the sun gear and the stator may be braked for a low speed forward drive from said rotor to said driven shaft, a friction brake for said carrier and said rotor for reverse drive, and a friction clutch for connecting together two elements of said planetary gear set` for a direct drive from said rotor to said Vdriven shaft, said friction brakes comprising a pair of coaxial drums disposed adjacent each other and a friction band adapted to engage each of the drums, said friction coupling comprising a plurality of interleaved friction plates disposed in the drum for said stator brake and said friction clutch comprising a plurality of interleaved friction plates disposed within the other of said drums.

DONALD W. KELBEL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

